Years ago I decided that in case I got the same question for at least three
times I would write down the answer and put it somewhere online in a more
or less public location that I can link to. The latest question I got once
too often came from daddies (mostly, sorry - not even a handful of moms
around me, let alone moms who are into tech) looking for ways to get there
children in touch with technology.

There are several obvious paths, including Lego Mindstorms,
the programming kits by Fischertechnik, several electronics kits you get at your
favourite shop, fun stuff like Makey,
makey kits that can turn a banana into a controller. Also many games come
with their own level designers (think Little Big Planet, though the older
children might remember that even Far Cry, Doom and friends came with level
designers).

In addition by now there are quite a few courses and
hacking events that kids are invited to go to - like the FrogLabs co-located with FrosCon, the Chaos macht Schule initiative by CCC, meetups
like the ones hosted by Open Tech
School, Jugend Hackt. In addition
quite a few universities collaborate with schools to bring pupils in
touch with research (and oftentimes tech) - like e.g. at HU Berlin.

In addition there are a three more less typical recommendations:

As a child I loved programming a turtle (well, a white dot really) to move
across the screen forward or backwards, to turn east, south, west or north, to
paint or to stop painting. The slightly more advanced (both in a graphical as
well as in an interactive sense of the word) version of that would be to go for
Squeak (all smalltalk, first heard about it
about a decade ago at the Chemnitzer Linuxtage) or Scratch (a geek dad kindly showed that to me
years ago).

When it comes to hardware hacking one recommendation I can give from
personal experience is to take part in one of the soldering courses by Mitch Altman - you know,
the guy who invented the "TV-B-Gone". Really simple circuits, you solder
yourself (no worries, the parts are large and robust enough that breaking them
is really, really, really hard). What you end up with tends to be blinking and
in some cases is programmable. As an aside: Those courses really aren't only
interesting for little ones - I've seen adults attend, including people who are
pretty deep into Java programming and barely ever touch circuits in their daily
work.

If you are more into board games: Years ago one of my friends invited me to
a RoboRally session.
Essentially every player programs their little robot to move across the board.

When it comes to books one piece I can highly recommend (didn't know something
like that existed until my colleagues came up with it) would be the book "Geek
Mom" - there's also an edition called "Geek Dad". Be warned though, this is not
tech only.

If you know of any other events, meetups, books or games that you think should
really go on that list, let me know.